Your plan and billing information are managed externally

I was also facing the same issue - https://www.dropboxforum.com/t5/Plans-and-Subscriptions/Dropbox-India-UPI-Payment-failed-and-unable-to-change-the/m-p/635654/highlight/true#M16754 

So did they have to fix something on their end for you to finally be able to upgrade?

I was able to fix this by Upgrading through the Dropbox iPhone App.  I believe that the iTunes/Apple Store is what managed my account externally.  

I am frustrated by facing this error while re-subscribing/upgrading my plan to dropbox plus. I tried all the options mentioned on community forum like trying to re-subscribe from different browser/incognito mode/by changing email address. Also, I couldn't find payment method in billing section to change it as per one of community answer. I did chat with support twice. Both of them couldn't help. I need to work on dropbox files urgently. Can someone from support look into this matter and help me to resolve this.  

Hey Shivam2, sorry to hear you're having issues with this.

Since you already contacted our support team, could you share your ticket ID so that we can look them up in our system? 

I have cancelled my monthly subscription through Google Play (which I have had for years) in order to sign up for a yearly subscription through Dropbox.com. Dropbox now asks me to upgrade (since my Google Play subscription has ended) and when I try to do that, I only get an error message ("Your plan and billing information are managed externally."). There is nothing else I can do. I removed the Google Play subscription completely and tried logging in via a different browser/incognito mode (as one solution on here suggests). So far, nothing has worked. What is particularly frustrating is that I cannot contact Dropbox support because I am on a basic plan now. I have been a paying customer for years and I intend to remain one, but I cannot seem to get any help with this from Dropbox directly.

Hannah I need help with my Dropbox existing paid account urgently.

I contacted you three weeks ago about being unable renew my Dropbox subscription after trying to move the payment from Apple to Dropbox directly.

You said there was nothing you could do at this time and that I should allow the Apple subscription to expire and then renew my sub via Dropbox. I express concern in that chat that allowing my sub to expire was risky and you said it would be fine. 

Now my account is cut off and my work files are no longer syncing.

I cannot renew with Dropbox (error: Your plan and billing information are managed externally) an I cannot renew with Apple (error: There was an error. Please try later). I have tried with multiple working cards. I have tried a private browser window.

I can no longer access live chat for help as I don't have a subscription. My work files are no longer syncing and I am totally stuck without access to my work files. I need assistance to get my account operating again asap please.

I still cannot upgrade, not in a different browser, not in a private window. This is starting to use up a lot of my time and I need to be able to sync between computers asap. I could migrate my files to a different Dropbox account, but I think it is easier to just use a different cloud service altogether. (Sorry for the  tone but it is driving me nuts that I cannot even contact support about this.)